The average atomic mass of Eu is 151.96 amu. There are only two naturally occurring isotopes of europium, 151Eu with a mass of 151.0 amu and 153Eu with a mass of 153.0 amu. The natural abundance of the 131Eu isotope must be approximately a. 60%. b. 20%.c. 50%. d. 80%. e. 40%.

Not all tiles will be usedidentify the element present in each star based on the gaps observed in wavelengths of its light refer to this table containing absorption wavelengths (in nm) of several different elements the table ishelium 447, 502 ,587 ,668carbon 427 ,515, 600 ,678sulfur 425, 565, 639, 675xenon 484, 590, 687calcium 429 ,527, 593, 645silver 421 ,521, 662

The ballistic pendulum was invented in 1742 by english mathematician benjamin robins. it consists of an initially stationary pendulum that moves after being struck by a bullet, and it is used to measure the original velocity of the bullet. the known variables are the bullet's mass m, the pendulum's mass m, and the height to which the block and bullet swing, determined by the length of the pendulum l and final angle θ. two principles of physics are necessary to solve for the bullet's original velocity. what are these principles? conservation of momentum and newton's third law conservation of energy and conservation of angular momentum grade summary deductions 0% potential 100% conservation of momentum and newton's second law. newton's second law and conservation of angular momentum. conservation of energy and newton's third law conservation of momentum and conservation of angular momentum. conservation of momentum and conservation of energy conservation of energy and newton's second law.

If a sphere and a cure have the same mass and are propelled up a ramp with the same force, which would travel father up the ramp? explain.